Increasingly, providers of teleconferencing services are using IP based teleconference bridges that require teleconference calls to be processed in a packet network infrastructure, e.g., a VoIP network infrastructure. Calls into these IP based conference bridges often originate in the Public Switched Telephone Network (PSTN) via toll free numbers, i.e., traversing the TDM network and crossing over into the VoIP network for termination. Due to the relative newness of the IP based teleconference services and VoIP technologies, adequate capacity to support high volume teleconferences is often not readily available in the new VoIP infrastructures. The capacity limitation issue may result from a high number of simultaneous call setups, originating from a PSTN switch, occurring at the beginning of a high volume conference call.
Therefore, a need exists for a method and apparatus for staggering Internet Protocol (IP) teleconferencing calls via a Public Switched Telephone Network (PSTN).